diff --git a/rigs/kenwood/kenwood.c b/rigs/kenwood/kenwood.c
index bcf160ad5..9713d24b2 100644
--- a/rigs/kenwood/kenwood.c
+++ b/rigs/kenwood/kenwood.c
@@ -2249,6 +2249,17 @@ int kenwood_set_level(RIG *rig, vfo_t vfo, setting_t level, value_t val)
 
     case RIG_LEVEL_RF:
         /* XXX check level range */
+        // KX2 and KX3 have range -190 to 250
+        if (val.f > 1.0) return -RIG_EINVAL;
+        if (RIG_IS_KX2 || RIG_IS_KX3) {
+            val.f = val.f * (250.0 - 190.0) + 190;
+        }
+        else if (RIG_IS_K3 || RIG_IS_K3S) {
+            val.f = val.f * (250.0 / 100.0);
+        }
+        else { // other kenwood rigs
+            val.f = val.f * 255.0;
+        }
         snprintf(levelbuf, sizeof(levelbuf), "RG%03d", kenwood_val);
         break;
 
@@ -2369,7 +2380,7 @@ int kenwood_set_level(RIG *rig, vfo_t vfo, setting_t level, value_t val)
     return kenwood_transaction(rig, levelbuf, NULL, 0);
 }
 
-int get_kenwood_level(RIG *rig, const char *cmd, float *f)
+int get_kenwood_level(RIG *rig, const char *cmd, value_t *val)
 {
     char lvlbuf[10];
     int retval;
@@ -2378,7 +2389,7 @@ int get_kenwood_level(RIG *rig, const char *cmd, float *f)
 
     rig_debug(RIG_DEBUG_VERBOSE, "%s called\n", __func__);
 
-    if (!f)
+    if (!val)
     {
         return -RIG_EINVAL;
     }
@@ -2392,7 +2403,8 @@ int get_kenwood_level(RIG *rig, const char *cmd, float *f)
 
     /* 000..255 */
     sscanf(lvlbuf + len, "%d", &lvl);
-    *f = lvl / 255.0;
+    val->i = lvl; // raw value
+    val->f = lvl / 255.0; // our default scaling of 0-255
     return RIG_OK;
 };
 
@@ -2560,7 +2572,7 @@ int kenwood_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
          * which is val=1.0 on most rigs, but
          * get_kenwood_level maps 0...255 onto 0.0 ... 1.0
          */
-        ret = get_kenwood_level(rig, "PC", &val->f);
+        ret = get_kenwood_level(rig, "PC", val);
         val->f = val->f * (255.0 / 100.0);
         return ret;
 
@@ -2626,15 +2638,15 @@ int kenwood_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
             break;
 
         case 1:
-            return get_kenwood_level(rig, "AG", &val->f);
+            return get_kenwood_level(rig, "AG", val);
             break;
 
         case 2:
-            return get_kenwood_level(rig, "AG0", &val->f);
+            return get_kenwood_level(rig, "AG0", val);
             break;
 
         case 3:
-            return get_kenwood_level(rig, vfo == RIG_VFO_MAIN ? "AG0" : "AG1", &val->f);
+            return get_kenwood_level(rig, vfo == RIG_VFO_MAIN ? "AG0" : "AG1", val);
             break;
 
         default:
@@ -2644,13 +2656,23 @@ int kenwood_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
         }
 
     case RIG_LEVEL_RF:
-        return get_kenwood_level(rig, "RG", &val->f);
+        retval = get_kenwood_level(rig, "RG", val);
+        if (retval != RIG_OK) return retval;
+        // KX2 and KX3 have range 190 to 250
+        if (RIG_IS_KX2 || RIG_IS_KX3) {
+            val->f = (val->i - 190) / (250-190);
+        }
+        else if (RIG_IS_K3 || RIG_IS_K3S) {
+            val->f = val->i / 250.0;
+        }
+        // other kenwod rigs are the default 0-255
+        return retval;
 
     case RIG_LEVEL_SQL:
-        return get_kenwood_level(rig, "SQ", &val->f);
+        return get_kenwood_level(rig, "SQ", val);
 
     case RIG_LEVEL_MICGAIN:
-        ret = get_kenwood_level(rig, "MG", &val->f);
+        ret = get_kenwood_level(rig, "MG", val);
 
         if (ret != RIG_OK)
         {
@@ -2662,8 +2684,8 @@ int kenwood_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
         return RIG_OK;
 
     case RIG_LEVEL_AGC:
-        ret = get_kenwood_level(rig, "GT", &val->f);
-        agclevel = 255 * val->f;
+        ret = get_kenwood_level(rig, "GT", val);
+        agclevel = val->i;
 
         if (agclevel == 0) { val->i = 0; }
         else if (agclevel < 85) { val->i = 1; }
diff --git a/rigs/kenwood/kenwood.h b/rigs/kenwood/kenwood.h
index 4dab795be..2c09a924e 100644
--- a/rigs/kenwood/kenwood.h
+++ b/rigs/kenwood/kenwood.h
@@ -27,7 +27,7 @@
 #include <string.h>
 #include "token.h"
 
-#define BACKEND_VER "20200917"
+#define BACKEND_VER "20200930"
 
 #define EOM_KEN ';'
 #define EOM_TH '\r'
@@ -80,6 +80,9 @@ extern const struct confparams kenwood_cfg_params[];
 #define RIG_IS_HPSDR     (rig->caps->rig_model == RIG_MODEL_HPSDR)
 #define RIG_IS_K2        (rig->caps->rig_model == RIG_MODEL_K2)
 #define RIG_IS_K3        (rig->caps->rig_model == RIG_MODEL_K3)
+#define RIG_IS_K3S       (rig->caps->rig_model == RIG_MODEL_K3S)
+#define RIG_IS_KX2       (rig->caps->rig_model == RIG_MODEL_KX2)
+#define RIG_IS_KX3       (rig->caps->rig_model == RIG_MODEL_KX3)
 #define RIG_IS_THD7A     (rig->caps->rig_model == RIG_MODEL_THD7A)
 #define RIG_IS_THD74     (rig->caps->rig_model == RIG_MODEL_THD74)
 #define RIG_IS_TS2000    (rig->caps->rig_model == RIG_MODEL_TS2000)
@@ -204,7 +207,7 @@ int kenwood_set_trn(RIG *rig, int trn);
 int kenwood_get_trn(RIG *rig, int *trn);
 
 /* only use if returned string has length 6, e.g. 'SQ011;' */
-int get_kenwood_level(RIG *rig, const char *cmd, float *f);
+int get_kenwood_level(RIG *rig, const char *cmd, value_t *val);
 int get_kenwood_func(RIG *rig, const char *cmd, int *status);
 
 extern const struct rig_caps ts950s_caps;
diff --git a/rigs/kenwood/ts2000.c b/rigs/kenwood/ts2000.c
index f36b012b9..7095b81a7 100644
--- a/rigs/kenwood/ts2000.c
+++ b/rigs/kenwood/ts2000.c
@@ -1066,7 +1066,7 @@ int ts2000_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
 
 
     case RIG_LEVEL_AGC: /* FIX ME: ts2000 returns 0 -20 for AGC */
-        ret = get_kenwood_level(rig, "GT", &val->f);
+        ret = get_kenwood_level(rig, "GT", val);
         agclevel = 255.0 * val->f;
 
         if (agclevel == 0) { val->i = 0; }
diff --git a/rigs/kenwood/ts870s.c b/rigs/kenwood/ts870s.c
index d14a3e111..16d4be682 100644
--- a/rigs/kenwood/ts870s.c
+++ b/rigs/kenwood/ts870s.c
@@ -481,19 +481,19 @@ static int ts870s_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
 
 
     case RIG_LEVEL_AF:
-        return get_kenwood_level(rig, "AG", &val->f);
+        return get_kenwood_level(rig, "AG", val);
 
     case RIG_LEVEL_RF:
-        return get_kenwood_level(rig, "RG", &val->f);
+        return get_kenwood_level(rig, "RG", val);
 
     case RIG_LEVEL_SQL:
-        return get_kenwood_level(rig, "SQ", &val->f);
+        return get_kenwood_level(rig, "SQ", val);
 
     case RIG_LEVEL_MICGAIN:
-        return get_kenwood_level(rig, "MG", &val->f);
+        return get_kenwood_level(rig, "MG", val);
 
     case RIG_LEVEL_AGC:
-        ret = get_kenwood_level(rig, "GT", &val->f);
+        ret = get_kenwood_level(rig, "GT", val);
         agclevel = 255 * val->f;
 
         if (agclevel == 0) { val->i = 0; }
diff --git a/rigs/kenwood/ts990s.c b/rigs/kenwood/ts990s.c
index d13c42798..c3eb269ca 100644
--- a/rigs/kenwood/ts990s.c
+++ b/rigs/kenwood/ts990s.c
@@ -561,7 +561,7 @@ int ts990s_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
         break;
 
     case RIG_LEVEL_MICGAIN:
-        retval = get_kenwood_level(rig, "MG", &val->f);
+        retval = get_kenwood_level(rig, "MG", val);
 
         if (retval != RIG_OK)
         {
@@ -670,7 +670,7 @@ int ts990s_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
         break;
 
     case RIG_LEVEL_VOXGAIN:
-        retval = get_kenwood_level(rig, "VG00", &val->f);
+        retval = get_kenwood_level(rig, "VG00", val);
 
         if (retval != RIG_OK)
         {
@@ -680,7 +680,7 @@ int ts990s_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
         break;
 
     case RIG_LEVEL_ANTIVOX:
-        retval = get_kenwood_level(rig, "VG00", &val->f);
+        retval = get_kenwood_level(rig, "VG00", val);
 
         if (retval != RIG_OK)
         {
diff --git a/src/iofunc.c b/src/iofunc.c
index 2aef03dc9..40621af90 100644
--- a/src/iofunc.c
+++ b/src/iofunc.c
@@ -665,7 +665,7 @@ int HAMLIB_API read_string(hamlib_port_t *p,
     struct timeval tv, tv_timeout, start_time, end_time, elapsed_time;
     int total_count = 0;
 
-    rig_debug(RIG_DEBUG_TRACE, "%s called\n", __func__);
+    rig_debug(RIG_DEBUG_TRACE, "%s called, rx_max=%ld\n", __func__, rxmax);
 
     if (!p || !rxbuffer)
     {
@@ -766,6 +766,7 @@ int HAMLIB_API read_string(hamlib_port_t *p,
         }
 
         ++total_count;
+        rig_debug(RIG_DEBUG_TRACE, "%s: total_count=%d rxmax-1=%ld\n", __func__, total_count, rxmax-1);
 
         if (stopset && memchr(stopset, rxbuffer[total_count - 1], stopset_len))
         {
diff --git a/src/serial.c b/src/serial.c
index 7104f4ec0..e507edce3 100644
--- a/src/serial.c
+++ b/src/serial.c
@@ -677,7 +677,16 @@ int ser_open(hamlib_port_t *p)
             /*
              * pathname is not uh_rig or uh_ptt: simply open()
              */
-            ret = OPEN(p->pathname, O_RDWR | O_NOCTTY | O_NDELAY);
+            int i;
+            for(i=0, ret=-1;i<5 && ret < 0;++i)
+            {
+                ret = OPEN(p->pathname, O_RDWR | O_NOCTTY | O_NDELAY);
+                if (ret < 0) {
+                    rig_debug(RIG_DEBUG_ERR, "%s: OPEN attempt#%d failed %d=%s\n", __func__, i+1, ret, strerror(errno));
+                    hl_usleep(100*1000); // 100ms between attempts
+                }
+            }
+
         }
     }
     if (ret == -1)